Biliary Disease
Gallbladder and Biliary Tree
• Imaging Studies Available
– X-ray
– Computed tomography
– Radioisotope scan (hepatobiliary scan)
– Ultrasound: the most sensitive study for
gallstone
Gallstones
• 81% consist of cholesterol and are
radiolucent (cannot be seen on plain films)
• 19% contain calcium and are radioopaque (can be seen on plain films)
Gallstones
• Size: can be very small (1-2 mm) to very
large (several cm)
• Shape: single stone – round, large
• Multiple stones – small, faceted
Gallstones
• Complications include
– Obstruction of bile duct: commonly cystic duct
and common bile duct
– Cholecystitis (infection/ inflammation of the
gallbladder)
– Abscess (complication of cholecystistis)
– Perforation:
• peritonitis, inflammation infection of peritoneum
• gallstone ileus, stone erodes into GI tract and
causes obstruction
Gallbladder
• Ultrasound
– Stones all appear ECHOGENIC (white)
• May be either radiolucent or radio-opaque
– Beyond stone is an acoustic shadow
– Bile is HYPOECHOIC (black)
– Polyps, neoplasm typically are isoechoic
(equal echo density) to adjacent soft tissues
Gallstones
• AP abdomen
• Several facetted
calcified densities
• Dense rim less
dense center
• Separate from
renal calculi and
costocartilage by
different positions
• Use oblique films,
gallbladder
anterior so move
away from spine
Gallstones
• Ultrasound upper
abdomen
• Longitudinal
scan
• Round
echogenic
structures in
gallbladder
• Acoustic
shadowing
Dilation of Bile Ducts
• Causes include
– Stone (most common)
– Carcinoma
Dilated Common Bile Duct
• Longitudinal US
through liver hilum
• Typical double
channel sign
• Dilated common bile
duct (blue arrow)
anterior to portal vein
(red arrow)
• Duct usually smaller
than vein
• Stone(not seen) distal
in duct
Bile Duct Dilatation
• Axial CT midabdomen
• Dilated common
bile duct
(arrowhead)
• Dilated intrahepatic
ducts
• Round fluid
structure anterior to
kidney is distended
gallbladder
Common Bile Duct Stone
• Axial imaging
lower than prior
example
• High density
structure
obstructing
calculi (arrow)
• Large round
area gallbladder
HIDA Imaging
• Radionuclide targeted
to hepatocytes
• Non filling of the
common bile duct or
gall bladder indicates
obstructive process
Acute Cholecystitis
• No filling of the gallbladder 60 minutes
after injection of isotope
• Rapid accumulation within the liver and
bile ducts with spill into the doudenum
Bile Leak Ida Scan
Accumulation of isotope outside of the biliary
tree
MR Cholangiography Stone
• Emerging
technology
• Visualize stone as a
filling defect in the
common duct (blue
arrow)